It is well known to input video data into a computer system. As indicated in US Patent Application Publication US 20012/0043282 for Hu, video capture chips are used for capturing still image or live video, and may be used together with a video sensor and signal processing circuit to form a video camera. While it is desirable to include a USB interface in the video capture chip to interface with a computer, the typical USB interface has a much smaller signal bandwidth capacity than the camera generates.
USB video capture devices are also well known for converting analog video signals to digital signals as a bridge between the PC and the camera. However, typical video capture devices process only a single signal. While in development, at present, a USB interface has a bandwidth of about 480 MB per second. It is anticipated that future devices will have 4.8 MB per second allocated to a single channel. In order to capture live video at a high resolution, the image data may be compressed using an intermediate buffer for compression of video data, but such a process as typically performed is undesirably costly. USB video capture devices including software for converting analog video signals to digital signals are also well known for inputting video data into a PC. As addressed by Hu, it is desirable to have a method and system for capturing video images with improved efficiency and reduced hardware costs.
It is also desirable to be available to process multiple signals. By way of further example, it will be useful to be able to provide input from multiple cameras to a single USB port at a high frame rate, and do so without the need for external signal processing.